Just to fill in some details... The (airport) "Roissybus" express all the way into town from every terminal is usually the fastest, and then the walk to the PH is fine, unless it's pouring rain. It and the RER both cost about 8 euros. Sometimes you can catch an express RER "B" train out to the airport, 31-33 minutes from Gare du Nord or Chatelet. (I timed it one early morn.) Mostly, it's not express. But taking it in from CDG at about 9:00am means you'll be joined by A LOT of commuters along the way. It might be a challenge unless you live with your rollaboard enough that it's like an appendage (not re safety, but rather the dance required in stuffed public transportation).

The Hyatt CDG's free bus leaves the Hyatt at 10:00am and gets to avenue de l'Opera in about 45 minutes. It departs avenue de l'Opera back to the Hyatt CDG at 6:00pm, sharp. No stops along the way, either direction. No Sunday RT. It's the same time/distance walk as from the Roissybus terminus to the PH. One could take the Hyatt CDG shuttle (well-marked, every 15 minutes, and Hyatt-only) from the airport to that Hyatt and then catch the Hyatt bus into town. Not if the plane arrives at 9:00am, but if that's the time by which you've collected luggage and cleared immigration.

Shame only that the Hyatt CDG bus doesn't just go directly to the Vendome PH, instead. But then people would want to go all the way from/to the airport, and, and... and then again, there are the people staying at the Madeleine.

By the way, the Hyatt CDG is quite a sight in itself, if you haven't seen it, and I think there is free coffee in the bar in the morning.

Also by the way, the SuperShuttle-type (they're not "SuperShuttle") shared-ride vans at CDG get bad reviews - even when reserved ahead - from a variety of people over in the TripAdvisor forums. Bon voyage.